We report on the characterization of the behaviour of an anisotropic magnetoresistive sensor undergoing a 100 kHz flipping of the magnetic domains, i.e. at frequencies two/three orders of magnitude higher than conventionally recommended. The noise analysis allows for the optimal setting of the relevant parameters defining such high-frequency, and hitherto unexplored, operation regime. Precision and accuracy performance in static conditions have been assessed by keeping into account the role of the sensor temperature. This last parameter has been evaluated by suitably manipulating the signals occurring at the sensor itself. The used technique can provide the base for a temperature sensor conditioning to be employed in magnetometers using this kind of devices.